Abstract: A heat pump and a control method thereof, the control method of the heat pump which heats a heated space through heat exchange between outdoor air and a refrigerant and heat exchange between the refrigerant and circulation water, includes calculating the maximum allowable frequency of a compressor based on the temperature of the outdoor air and the heating load of the heated space, calculating the mean operating frequency of the compressor while the compressor is operated at the calculated maximum allowable frequency, recalculating the maximum allowable frequency based on a result of comparison between the mean operating frequency and the maximum allowable frequency, and operating the compressor at the recalculated maximum allowable frequency, thereby improving coefficient of performance (COP) of the heat pump.

Abstract: A heat pump and a control method thereof, the control method of the heat pump which heats a heated space through heat exchange between outdoor air and a refrigerant and heat exchange between the refrigerant and circulation water, includes calculating the maximum allowable frequency of a compressor based on the temperature of the outdoor air and the heating load of the heated space, calculating the mean operating frequency of the compressor while the compressor is operated at the calculated maximum allowable frequency, recalculating the maximum allowable frequency based on a result of comparison between the mean operating frequency and the maximum allowable frequency, and operating the compressor at the recalculated maximum allowable frequency, thereby improving coefficient of performance (COP) of the heat pump.

Abstract: Disclosed are a heat pump boiler and a control method for the same. The heat pump boiler includes an outdoor unit having an outdoor-unit heat-exchanger, a water pipe including a water-feed pipe and a water-return pipe connected to the outdoor unit to feed water to the outdoor unit or to return low-temperature or medium-temperature water produced in the outdoor unit to an external location, heat exchangers connected to the water pipe to produce medium-temperature or high-temperature water, a variable-capacity compressor connected to the heat exchangers, a buffer tank connected to the water pipe, and an externally-wound heat exchanger to collect waste heat radiated from the compressor. A temperature of water stored in the buffer tank is raised using the collected waste heat, and, during a defrosting operation, the water stored in the buffer tank is fed to the outdoor-unit heat-exchanger to defrost an evaporator of the outdoor unit.

Abstract: An air conditioner controls supply of refrigerant so that the refrigerant is first supplied to one or more indoor units in operation from an outdoor unit, and is then supplied to a hot water generator, thereby sufficiently supplying refrigerant to the indoor units in heating operation even when the hot water generator is operated.

Abstract: A heat pump system which executes cooling and heating operations of an A2A indoor unit and cooling and heating operations and a hot water operation of an A2W indoor unit in a time division multiplexing (TDM) method, and a control method thereof. Further, the heat pump system solves shortage of a refrigerant during a heating operation of the A2A indoor unit or the A2W indoor unit when the TDM method is used. Therefore, the heat pump system includes a control unit to alternately operate the A2A indoor unit or the A2W indoor unit, upon judging that a simultaneous operating condition of the A2A indoor unit or the A2W indoor unit is satisfied. The heat pump system further includes a refrigerant distribution unit to circulate a refrigerant selectively to the A2A indoor unit or the A2W indoor unit.

Abstract: A heat pump system, the operation of which is controlled using a temperature difference between a water inlet and a water outlet of a heat exchanger, exchanging heat between a refrigerant and water, and a control method thereof. The heat pump system includes temperature sensors installed on a water circulation pipe unit at water inlet and outlet sides of a heat exchanger, and heats a load to a set temperature by controlling a compressor or an expander according to a difference between temperatures sensed by the temperature sensors. Here, a temperature of water transmitted to the load is set to be greater than a target load temperature by a reference value, and if the temperature difference is smaller than a designated value, the operation of the heat pump system is stopped.